Cut-off device

ABSTRACT

A rotary shear or cut-off device for web fed materials such as paper napkin stock that includes a novel adjusting means, the device being capable of operating at high speeds without difficulties, and wherein all four edges of the knife, such as the anvil knife, can be used, and wherein chamfered edges are utilized on the anvil knife and fly knife.

United States Patent Trogan et al. [451 Jan. 9, 1973 54 CUT-OFF DEVICE2,723,604 11/1955 Fischer ..83/345 x [75] Inventors: John F. Trogan,Ashland; James H. Beebe, 0f [73] Assignee: C. G. Bretting ManufacturingCo., 312471746 4/1966 Inc. McGrath.. 3,302,503 2/1967 Hornung ..83/345 X[22] Filed: March 1, 1971 Primary Examiner-Frank T. Yost [2]] Applll9614 Att0rneySherman Levy [52] U.S. Cl. ..83/152, 83/342, 83/345, [57]ABSTRACT [51] int Cl A rotary shear or cut-off device for web fedmaterials [58] Field 345 A 674 673 such as paper napkin stock thatincludes a novel ad- 85/672 69 justing means, the device being capableof operating at high speeds without difficulties, and wherein all [56]References Cited four edges of the knife, such as the anvil knife, canbe UNITED STATES PATENTS used, and wherein chamfered edges are utilizedon the anvil knife and fly knife.

9 Claims, 8 Drawing Figures PATENTEDJAF! 9 I975 SHEET 1 [1F 2 INVENTORS\TO/IIV E 77206.4 F 11 M455 A 56586 BY ATTORNEY PATENTED JAN 9 I975SHEET 2 OF 2 INVENTORS f m Z M hi CUT-OFF DEVICE The present inventionrelates to a cut-off device for web fed materials such as paper napkinstock.

An object of the present invention is to provide a rotary shear orcut-off device for web fed material such as paper napkin stock whereinthe device or mechanism is relatively simple in construction and easy toadjust, and wherein the device is constructed so that it can run oroperate at high speeds without any ill effects, and wherein in thesystem of the present invention the percent of over speed of the flyknife roll is not critical and this is advantageous because it permitsthe roll diameter of the fly knife roll to be increased in the eventdeflection becomes a problem due to a short cut off length.

Another object of the present invention is to provide a cut-off devicewherein all four edges of the anvil knife can be used, and wherein thereis provided a novel gear arrangement for the cut-off system or rotaryshear of the present invention.

Still another object is to provide a cut-off system that is animprovement over such prior systems or devices as those shown in priorU.S. Pat. Nos. 2,478,240 and 3,247,746.

Another object is to provide a cut-off system that is adapted tominimize errors productive of wasted labor and material in the formationthereof, and further objects and advantages are to provide improvedelements and arrangements thereof in a device of the character describedthat is relatively economical to produce, durable in form, and conduciveto the most economical use of materials and uniformity of members formedtherefrom.

Further objects and advantages will become apparent in the subsequentdescription in the specification.

In the drawings:

FIG. I is an end view of the gearing device of the present invention.

FIG. 2 is a sectional view taken on the line 2-2 of FIG. 1.

FIG. 3 is a fragmentary sectional view taken through the fly knife rolland anvil knife roll at the beginning of a cut.

FIG. 4 is a view generally similar to FIG. 3, but with the parts rotatedtowards the end ofa cut.

FIG. 5 is an exploded perspective view of the fly roll and itsassociated parts.

FIG. 6 is a side view of the fly knife.

FIG. 7 is an exploded perspective view of the anvil knife and itsclamping means.

FIG. 8 is an end view of the anvil knife.

Referring in detail to the drawings, the numeral indicates the rotaryshear or cut-off device of the present invention, and the rotary shearis adapted to be used'for cutting paper napkin stock and the like whichis held against the surface of the vacuum roll 21 by a vacuum means orthe like. The vacuum means is actually a series of small holes(one-eighth inch to five thirty-seconds inch) through clean out plate30A.

As shown in the drawings, such as in FIG. 3, the vacuum roll 21 holds ananvil knife 22. The numeral 23 indicates a single repeat roll thatcarriesa fly knife 24, and the numeral 25 indicates a fly knife or bladeholder. As shown in the drawings, a wedging or angle block 26 isprovided adjacent the holder 25 and. the adjustment of these partsdetermines the angle of the fly knife 24 with the center line of therepeat roll 23. The fly knife 24 is adapted to be adjusted by finethreaded set screws or securing elements 43 and 44. The anvil blade 22has chamfered edges 31 thereon, FIG. 8, and this chamfer 31 may have asuitable configuration such as 45 0.042 inches, and runs along theentire length on all four sides.

The fly knife blade 24 has a chamfered corner 29, FIGS. 5 and 6, to helpit get under the anvil blade 22. Four corners 31 of the anvil knife 22are adapted to be chamfered across the entire cutting edge on all foursides for use on all four sides of the knife or device.

As shown in the drawings, such as in FIG. 2, the vacuum roll 21 and flyknife roll 23 are mounted on shafts l9 and 18, respectively, that rotatein bearings 32, and the bearings 32 may be supported by a suitable frameor supporting structure 33 of a desired configuration or formation.

As shown in FIG. 2, there is provided a split gear 36 that consists ofgear members 34 and 35 that are mounted on the hub 37 for driving thefly knife roll gear 38 that is fixed to the roll journal by hub 39through the medium of bolts 40. The bolts 40 may extend through slots17.

Pins 41 are pressed into the gear 38 and extend into the hub 39 throughover-sized holes or openings. It will be noted that by loosening thebolts 40 and adjusting the set screws 42 on either side of the pins 41,a fine tune of the cutting edges can be obtained before the fly knifeblade set screws-43 and 44 are utilized.

As shown in the drawings, the one half gear 35 is fixed to the hub 37 bybolts 45, and the gear 35 does the driving of the fly knife roll gear38. The other half 34 of the vacuum roll gear is adjusted in a directionopposite to its rotation by loosening the bolts 46 and adjusting the setscrews 47 on either side of pin 48 so as to remove all of the backlashbetween these gears, as later described in this application.

It will be noted that the anvil blade 22 is held in place by block 49and clamped against the face of block 50 by slight loosening of thebolts 51 in block 49, and tightening of the bolts 52 in the wedgingblock 53 which slides the block 53 sideways down its tapered seat 54.

From the foregoing, itwill be seen that there has been provided a rotaryshear or cut-off'device which is especially suitable for cutting papernapkin stock and the like, and in use with the parts arranged as shownin the drawings, power can be supplied from any suitable source ofsupply so as to rotate the pair of rolls 21 and 23 towards each other,as indicated by the arrows 55 and 56 in FIGS. 3 and 4. As is well known,the paper napkin stock or other stock is held against the surface of theroll2l in any suitable manner. as for example, by means of a vacuumarrangement 30 which forms no part of the present invention.

The present invention thus consists of the vacuum roll 21 that holds theanvil knife 22, and there is further provided the single repeat roll 23which carries the fly knife 24. The fly knife 24 is held in place bymeans of a fly knife blade holder 25 that is maintained at its properlocation by means of the wedging or angle block 26, and the position ofthese parts determines the angle of the fly knife 24 relative to thecenter line of the roll 23.

The fly knife roll 23 is generally a single repeat roll, while thevacuum roll 21 may be used in repeats of two, three and four, as shownin dotted lines in FIG. 1, and no apparent ill effects are noticeable.The surface speed of the tip of the fly knife blade 24 may be used atfrom approximately 31% to 75% higher than the cutting edge of the anvilblade 22 with no shortcomings as to speed limitations,

The larger percent of over speed can be used on small repeat sizes toget a larger fly knife roll body to eliminate roll deflection problemsand the like.

With the present invention, the fly knife blade 24 is not being bowed orcurved as is the case in prior U.S. Pat. No. 3,247,746. The fly knifeblade 24 is adjusted by the fine threaded set screws 43 and 44 ingenerally a straight line until it acts with the anvil knife 22 and cutsthe web. One of the main aspects or features of the present invention isthe 45 X 0.042 inches chamfer 31 of the anvil blade 22, although it isto be understood that other configurations of the chamfer can be used onthe anvil blade. Heretofore, before this chamfer 31 was added orutilized, a very poor fly knife blade life resulted. in addition, flyknife blade 24 has a chamfered corner 29 on the leading edge to help itget under the anvil knife 22. This blade can be chamfered on all fourcorners for use on all four cutting edges. Further, the anvil knife 22is also chamfered across the entire cutting edge on all four corners foruse on all four corners. The anvil knife 22 may be made of a high speedtool steel of 66-68 Rockwell C", and the fly knife may be made fromeither a high speed steel or a Swedish high carbon spring steel. Whileboth work equally well, the use of spring steel provides certainadvantages from a point of view of cost.

It is to be noted that the vacuum roll 21 and the fly knife roll 23rotates in bearings such as bearings 32. There is provided a split gear36 that embodies or includes members 34 and 35 that are mounted on thehub 37, and this split gear arrangement drives the fly knife roll gear38 which is fixed to the roll journal by hub 39 through bolts 40. Pins41 are adapted to be pressed into the gear 38 and extend into the hub 39through oversized holes. By loosening the bolts 40 and adjusting the setscrews 42 on either side of the pin 41, a fine tune or adjustment of thecutting edges can be accomplished or obtained before the fly knife bladeset screws 43 and 44 are utilized.

in addition, the one-half gear 35 is fixed to the hub 37 by bolts 45,and the gear 35 does the driving of the fly knife roll gear 38. Theother half of the vacuum roll gear 34 is adjusted in a directionopposite to its rotation by loosening bolts 46 and adjusting the setscrews 47 on either side of the pin 48, in order to remove all of thebacklash between these gears.

It will be noted that the anvil blade 22 is held in place by the block49 and is clamped against the face of the block 50 by slight looseningof the bolts 51 in the block 49 and tightening of the bolts 52 in thewedge block 53 which slides the block 53 sideways down its tapered seat54. Bolts or screws 58 serve to connect the block 50 to the vacuum roll21, as shown in FIGS. 3 and 4.

It is to be understood that the parts can be made of any suitablematerial and in different shapes and sizes, as desired or required.

The present invention will permit high speed operations to be carriedout, and there is provided a rugged construction, and not only does theweb cut-off device of the present invention give extremely long life butis easily adjustable. Maintenance is minimized, and the machine isengineered for high speed operation, and in addition, versatility isassured.

With further reference to the present invention as compared to priorpatents, such as prior U.S. Pat. No. 3,247,746, it is to be noted thatthe present invention does not include a slot equipped plug in a slotenlargement, nor does it include holder means mounted in plug slots.Also the present invention is different from or an improvement over theconstruction of prior U.S. Pat. No. 3,247,746, inasmuch as it does notinclude the end plugs, the plug and screw arrangement, and the helixformation.

It will be noted that in the present invention there is a blade 24 withfour cutting edges held in a channelshaped holder, spaced at an anglerelative to the axis of the small roll by the wedging block 26, andfinal adjustment of this blade 24 is accomplished by using the setscrews 43 and 44. The matching knife or anvil blade 22 also has fourcutting edges 31 and has a 45 chamfer on each edge, which makes theblade easier to adjust. Thus, the present invention is relatively simplein construction and is very easy to adjust, and it is capable ofoperating at high speeds without any ill effects.

A further advantage of the present invention is that the percent of overspeed of the fly knife roll 23 is not critical. This is advantageous,because it permits the roll diameter of the fly knife roll 23 to beincreased should deflection be a problem due to a short cut off length,and the like.

The present invention has the advantage in that all four edges of theanvil knife 22 can be used. Due to the thickness and method of holding,this knife very seldom breaks, but it becomes dull after being used fora period of time.

Although the invention has been herein shown and described in what isconceived to be the most practical and preferred embodiment, it isrecognized that departures may be made therefrom within the scope of theinvention, which is not to be limited to the details disclosed hereinbut is to be accorded the full scope of the claims so as to embrace anyand all equivalent devices and apparatus.

1 claim:

1. in a web cut-off device for cutting paper napkin stock and the like,a vacuum roll and a fly knife roll, an anvil knife, and a fly knifemounted in said vacuum roll and fly knife roll. respectively, a holderfor said fly knife, a wedge block positioned adjacent said holder,adjustable set screws operatively connected to said fly knife roll andengaging said holder and wedge block, said anvil knife having chamferededges that run along its entire length on all four sides thereof, saidfly knife having chamfered corners thereon, and holding means for theanvil knife.

2. The structure as defined in claim 1, wherein said last-named holdingmeans comprises a block affixed to said vacuum roll, and a wedging blockand clamping block for said anvil knife.

3. The structure as defined in claim 1, and further including gearmeans.

4. The structure as defined in claim 1, and further including gear meansthat comprises split gear members, hubs associated with said gearmembers, and securing elements and pins operatively associated with saidgear means.

5. The structure as defined in claim 1, wherein the fly knife has achamfered corner on the leading edge to help it get under the anvilknife.

6. The structure as defined in claim 1, wherein the fly knife is adaptedto be chamfered on all four corners for use on all four cutting edges,and wherein the anvil knife is chamfered across the entire cutting edgeon all four corners for use on all four corners.

7. The structure as defined in claim 1, and further including gear meansthat comprises split gear members, one of said split gear members beingadjustable in a direction opposite to its rotation by loosening securingelements and adjusting said screws in order to remove all backlashbetween these gears.

8. The structure as defined in claim 1, wherein the holding means forthe anvil knife includes a block affixed to the vacuum roll, and thewedging block thereon.

9. A new article of manufacture, a web cut-off device for cutting papernapkin stock and the like, comprising a vacuum roll and a fly kniferoll, an anvil knife mounted in said vacuum roll, a fly knife mounted insaid fly knife roll, a holder for said fly knife, a wedge blockpositioned adjacent said holder, adjustable set screws operativelyconnected to said fly knife roll and engaging said holder and wedgeblock, said knives having chamfered edges and corners, holding means forthe anvil knife, said last-named holding means comprising blocks, one ofwhich has a tapered seat, said web cut-off device further including gearmeans that embodies split gear members, securing elements and pinsoperatively connected to said gear means, said fly knife having achamfered corner on the leading edge to help it get under the anvilknife, the anvil knife being chamfered across the entire cutting edge onall four corners for use on all four corners.

1. In a web cut-off device for cutting paper napkin stock and the like,a vacuum roll and a fly knife roll, an anvil knife, and a fly knifemounted in said vacuum roll and fly knife roll, respectively, a holderfor said fly knife, a wedge block positioned adjacent said holder,adjustable set screws operatively connected to said fly knife roll andengaging said holder and wedge block, said anvil knife having chamferededges that run along its entire length on all four sides thereof, saidfly knife having chamfered corners thereon, and holding means for theanvil knife.
 2. The structure as defined in claim 1, wherein saidlast-named holding means comprises a block affixed to said vacuum roll,and a wedging block and clamping block for said anvil knife.
 3. Thestructure as defined in claim 1, and further including gear means. 4.The structure as defined in claim 1, and further including gear meansthat comprises split gear members, hubs associated with said gearmembers, and securing elements and pins operatively associated with saidgear means.
 5. The structure as defined in claim 1, wherein the flyknife has a chamfered corner on the leading edge to help it get underthe anvil knife.
 6. The structure as defined in claim 1, wherein the flyknife is adapted to be chamfered on all four corners for use on all fourcutting edges, and wherein the anvil knife is chamfered across theentire cutting edge on all four corners for use on all four corners. 7.The structure as defined in claim 1, and further including gear meansthat comprises split gear members, one of said split gear members beingadjustable in a direction opposite to its rotation by loosening securingelements and adjusting said screws in order to remove all backlashbetween these gears.
 8. The structure as defined in claim 1, wherein theholding means for the anvil knife includes a block affixed to the vacuumroll, and the wedging block thereon.
 9. A new article of manufacture, aweb cut-off device for cutting paper napkin stock and the like,comprising a vacuum roll and a fly knife roll, an anvil knife mounted insaid vacuum roll, a fly knife mounted in said fly knife roll, a holderfor said fly knife, a wedge block positioned adjacent said holder,adjustable set screws operatively connected to said fly knife roll andengaging said holder and wedge block, said knives having chamfered edgesand corners, holding means for the anvil knife, said last-named holdingmeans comprising blocks, one of which has a tapereD seat, said webcut-off device further including gear means that embodies split gearmembers, securing elements and pins operatively connected to said gearmeans, said fly knife having a chamfered corner on the leading edge tohelp it get under the anvil knife, the anvil knife being chamferedacross the entire cutting edge on all four corners for use on all fourcorners.